deposit is 10 km NW of the settlement of Gromovka in the Chara district, former Semipalatinsk oblast. It is related to a zone of beryl-bearing, quartz-phlogopite greisen in the exocontact of the late Paleozoic Del'begetei granite massif. Emerald mineralization has been traced within sandstones, conglomerates, and carbonaceous shales of the Lower Carboniferous Bukon'skaya suite for a distance of more than 800 m and a thickness of 15 to 20 m. Emeralds
occur in two sections: Zapadnyi (Western) and Izumrudnye (Emerald).
Small prismatic crystals of the bluish emerald
, up to 5 mm in length, occur with light green beryl
, similar to aquamarine
. Larger emerald
crystals up to 2 cm long are found at the Izumrudnye section in lensoid vugs of quartz greisen, in an alpite dike associated with dark blue fluorite.
Ref: E.Ya. Kievlenko (2003) Geology of gems, p. 95